1. Field of the Invention
The present invention relates to an optical connector for connecting optical fibers, and more specifically to an optical fiber connector preferably applicable to a plug-in optical connector for removably connecting a number of package boards (on each of which various optical and electrical components or parts are mounted as a completed part subassembly) to a back panel perpendicular to the package board in book-shelf fashion to construct a high-density assembly unit.
2. Description of Prior Art
With the progress of higher optical performance in optical communication systems, a higher density assembly unit composed of so-called plug-in connectors is required more and more.
In the plug-in optical connector, it is required that a number of optical fibers must be simultaneously coupled to or decoupled from each other by a simple insertion and removal coupling operation. Further, since a number of optical fibers are coupled to each other under pressure within the connector housings, a certain connector housing locking mechanism is required to prevent the ferrule coupling pressure from being directly applied to the package board and the back panel via the connector housings.
Further, in an optical assembly unit, since a number of backage boards are connected to a back panel via plug-in connectors in book-shelf arrangement fashion, it is necessary to absorb an assembly error in the direction perpendicular to the axial direction of the optical connector element (plug and jack), without increasing the dimensions or the size of the optical connector.
In addition, since a number of optical connector elements (plug and jack) are simultaneously fitted to the plug-in optical connector, it is also necessary to absorb each dimensional and assembling error in the axial direction of the plug/jack. In absorption of the axial coupling error between the plug/jack and the connector, it is not preferable to increase the axial connector length; that is, it is necessary to stably support the plug/jack within the connector housing without increasing the axial length of the plug/jack.
Further, when an optical plug comprising a ferrule which is connected to an end of an optical fiber is fitted to the optical connector, a optical plug locking mechanism including elastic cantilever arm members with a claw at the free end thereof, are provided between the optical plug and the optical connector housing. However, since the locking mechanism is reduced in size more and more with increasing fiber arrangement density, it is necessary to more firmly lock the connector plug to the connector housing, even when a high tensile strength is applied to the optical fiber, in spite of a simple insertion and removal operation.
Further, when the optical plug is inserted into the optical connector, it is particularly preferable that the optical plug is easily fitted to the connector housing in a predetermined orientation to eliminate an axis alignment error between two mated optical ferrules in order to maintain high optical signal transmission characteristics.
Further, when an optical jack comprising a ferrule which is connected to an end of an optical fiber and an alignment sleeve is fitted to the optical connector, it is preferable that the ferrule end can be easily cleaned and further the ferrule alignment sleeve can be easily replaced with a new one, because the wear chip is produced within the ferrule alignment sleeve whenever the optical jack is coupled to or decoupled from the connector housing.
The structure and arrangement of the prior-art optical connector, plug, jack etc. will be described in more detail hereinafter with reference to the attached drawings under DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS.